Novel Citrus Fiber-Entrapped Curcuminoids Exhibit Improved Oral Bioavailability in Wistar Rats

Curcuminoids (Cmn) are polyphenolic compounds from Curcuma longa that exhibit significant pharmacological activities but suffer from poor bioavailability due to low solubility and rapid metabolism. We have developed a novel formulation of Cmn entrapped within citrus fibers with the intent to improve its bioavailability. The physiological properties of citrus fibers improve aqueous dispersion and apparent solubilization of Cmn while protecting it from physiological degradation. Single-dose oral pharmacokinetics in Wistar rats revealed that citrus fiber-entrapped Cmn (CurcXR) exhibited a 57.52-fold increase in bioavailability compared to 95% standard Cmn. The maximum plasma concentration (Cmax) of 0.95 μg/mL at 4 h, and an area under the curve (AUC0−t) of 8.84 μg/mL·h was observed for CurcXR. These findings highlight that citrus fiber-based formulations are a simple, safe, and effective strategy to enhance the bioavailability of Cmn in nutraceuticals.